Apparatus for producing vacuums.



(No Modal.)

Pig 2.

Fig.4.

\Mtnesses Patented July 9, I90l. J. W. HOWELL & W. B. BURR0WS. APPARATUS FOR PRODUCING VADUUMS.

(Application filed Apr. 5, 1900.)

'mzvuoams Farms :0 Fnofmuruo" WASHINGTON, n. c.

Jnventors: oh'n W. Howell, Wilham RBurrows the exhaustion of globes containing the fila- U ITED STATES PATENT OFFICE.

JOHN W. HOWELL AND WILLIAMv R. BURROWS, OF NEWARK, NEW JERSEY, ASSIGNORS TO THE GENERAL ELECTRIC COMPANY, OF NEW YORK.

APPARATUS FOR PRODUCING VACU'UMS.

SPECIFICATION forming part of Letters Patent No. 677,989, dated July 9,1901.

Application filed April 5, 1900. Serial No. 11 627. (No model.) I

To aZZ whom it may concern:

Be it known that we, JOHN W. HOWELL and WILLIAM R. BURRows, citizens of the United States, residing at Newark, county of Essex, Stateof New Jersey, have invented certain new and useful Improvements in Apparatus for Producing Vacuums, (Case No. 1,211,) of which the following is a specification.

This invention relates to apparatus for producing'high vacua. V

The invention is particularly applicable to ments of incandescent electric lamps, though it may be employed for other uses where high fected. The heater we employ is of a spevacua are desirable.

In producing vacua considerable difficulty is experienced in removing the last traces of air and of gases trapped or occluded, for eX-. ample, in the filaments and in the joints where such filaments are employed, as in incandescent electric lamps, and also in the re-- moval of the moisture which adheres to the.

walls of the globe or vessel being exhausted. We provide for the removal of these residual gases and of the moisture by subjecting the; vessel being exhausted to the; action of a. heater or oven of a convenient form, by which, the moisture clinging to'the inner walls is vap-f orized and driven out from the inclosureand' the residual gases are driven out. Prior to our invention heating of the vessel has been practiced; but our apparatus provides much greater convenience of manipulation and adds greatly to the comfort of the operator.

In carrying out our invention weprovid'e a: heater adapted to inclose the vessel being ex'-.-.

hausted, having an outer wall of poor heatradiating metal and provided at its bottom: with a gas-flame or series of jets so arranged of the heaters being-provided for each workman, so that one group of lamps may be subjected to heating action'while another group is being finished or sealed off. The heater.

' hot gases. in the heater.

is made sectional, so that one side of it may be readily removed to permit the insertion of anew group of lamps to be exhausted or to placed a drying agent, such as phosphoric an 'hydrid, said tube being placed in thepath of suction from the lamps to the pumps. The tube is provided with two pump connections,

one leading to a pump which carries on the preliminary exhaustion and the other to a pump by which the final exhaustion is efcial form of construction which we have found advantageous in practice,being divided 'on a median line lengthwise of the group of lamps to be exhausted and the two parts adapted to be connected together quickly by {means of a hook or other joint. The walls iare made of sheet-aluminium, which being Ea metal of poor heat radiating capacity @greatly increases the comfort of the operator :in manipulating the apparatus in reducing it-he heat thrown in his face and improves the faction of the heater and saves gas by better iconfiningthe heat and reducing the loss from rradiation. Therear or stationary portion of itheheateris provided with a gas-pipe at the.

ibot'tomperforated on top with a series of iholesto form a row of burners, above which g'is located a deflecting-wall to distribute the The rear portion of Ethe heater is mounted so that it may be adijusted vertically to, accommodate different gsizes of lamps or lamps having diflferent @lengths of stem. 7 lformed of a good heat-reflecting but poor iradiating material, such as sheet-aluminium,

; whichalso increases the lightness of the parts. %The walls may be stiffened by bracesor a frame of steel or iron. The phosphoric anhydrid is contained in a trough or tube supported concentrically within the outer tube,

the latter being provided'at intervals with tubular sockets to receive the stems of the lamps and the former being provided with openings on top through which the air and gases from the lam p-bulbs may be drawn dur= ing exhaustion.

The walls of the heater are tion, partly in section, of an exhausting apparatus embodying our improvements. Fig.

2 is a side elevation showing a group of lamps fixed in place in the heater, the removable section of the heater being withdrawn. Fig. 3 is a face view of the movable section of the heater. Fig. 4 is a sectional view of the traptube through which the exhausted gases and vapors pass on their way to the pumps. Fig. 5 is a cross-sectional view of this tube.

In fixed relation to the workmans table is a double tubular structure 1, provided with a row of nozzles 2 2 in a straight line flaring toward the top to receive the stem 3 3 of a group of lamps. In practice eight lamps are operated in a group, and the tube is provided with as many nozzles as will accommodate this number of lamps. The joint is made air-tight by a piece of rubber tubing fixed in the nozzles, into which the stem of the lamp is firmlyinserted. The conducting-Wires leading to the terminals of the filament are drawn into springclips, as indicated M44, the clips being mounted on an arm or lever pivoted on a support at the rear of the workmans table and thrown upwardly by a spring, so as to exert a light tension on the filament conductors. These clips are so arranged that they may be connected in a high-tension testing-circuit to test the final condition of the vacuum and also in a current-supply circuit to raise the filament to incandescence to drive oil? the gases occluded therein or in the joints. As this organization is of ordinary construction, we deem it unnecessary to illustrate or describe it in detail. The lamps are inclosed within a heater formed in two sections. The rear section 5 is provided with a rod or plate 6, which may be raised or lowered vertically by a pivoted handle 7 and secured in any desired position of adjustment by a set-screw 8, controlled by a thumb-nut 9, said screw being guided in a slot in a pivoted support 6", mounted on the tableand permitting the rear section of the heater to be tilted back away from the lamps. The walls of the heater are formed of sheet-aluminium, bent so as to form a fairly-tight casing around the lamps, and are separable on a plane parallel to the group of lamps. The rear section 5 may be lined with sheet-iron, the lower end of which projects below the row of burners formed in the gas-pipe 10. Above the burners and within the fixed section of the heater is a deflectingwall 11, which distributes the heated air and .gases from the flame and equalizes the distribution of heat within the heater. The front section of the heater is provided with hooks at its ends, as indicated at 19 in Fig. 1, adapted to rest on pins or lugs on the rear section when the two parts are brought together. The front section may be lined with a steel framework composed of a plurality of transverse ribs 12 12 and one or more longitudinal ribs 13, to one of which maybe riveted a handle 14,, by which the front section maybe manipulated. This handleshould be wrapped with asbestos or other fireproof non-conductorof heat to permit the workman to comfortably manage its removal from or replacement over the lamps. The tube through which the exhausted gases are drawn is provided at its end with removable screw-plugs 15 15 and is provided near one end with a tubular connection 16, opening into the bottom of the outer tube leading to the preliminary exhausting-pu m p. From each end of the tube is inserted a trough or second tube provided with supporting-feet, as indicated at 17 17, Fig. 5, to support it, so that its walls will be surrounded by a free space at all points within the outer tube. A series of openings is provided in the top of each inner tube or trough, and a central pump connection 18 is led to the final exhausting-pump, the end of this connection terminating below the top of each inner tube.

The construction described permits the easy removal of the inner tubes and renewal of the chemical employed to absorb the residual vapors when necessary. We prefer to employ for this purpose phosphoric anhydrid, which is placed within each trough, and the latter then inserted in the outer tube and the screw-plugs 15 15 adjusted to make an airtight joint. 7

In forming a vacuum a group of lamps is connected with the tube 1 and the terminals with the clips l 4: and the preliminary exhausting-pump set to work to remove most of the gaseous contents of the bulbs. The final pump connecting with the tube 18 is then set in operation and the sections of the heater brought together to inclose the lamps. The high temperature to which the lamp is subjected from the outside drives all moisture from the inner walls of the bulb, which is removed by the pump and absorbed in its transit toward the pump by the chemical contained inside the tube 1. At the final stage of the operation the filament may be raised to incandescence by closing the supply-circuit and any excess of gases occluded in the filament driven ofi and removed by suction or by other methods known to the art. The lamps being mounted on the support in a straight line permit convenient access of the operator to any lamp, either in mounting or removal. openings in the inner tubes are located, when the parts are assembled, between the lamp connections, thereby preventing the draft of exhausting gases from scattering the chemical and clogging the pumps. The tube 16,

leading to the preliminary pump, opens at the bottom of the outer tube, between which and the pump may be located a trap 20 for any particles of glass left in the bulb by the blowing, these particles naturally dropping to the bottom of the tube 1.

The

What we claim as new, and desire to secure by Letters Patent of theUnited States, is

1. Means for producing high vacua, comprising an exhausting pump, a sectional chamber inclosing a group of vessels to be exhausted with an intervening space, said chamber being separable onfa plane parallelto the group of lamps, and a source'of heat at thetional heater inelosing the lamps, the sections of the heater being separable on a plane par allel to the line of lamps, one section being removable from the lamps to permit easy manipulation. v

4:. Means for exhausting incandescent lamps, comprising an exhaustingpump, a

sectionalheater to inclose a group of lamps,

open at the bottom, a gas-burner communicating with the opening, and means for separating the sections to admitinsertion or withdrawal of the lamps. l

5. Means for producing high vacua, com-- prising a pump, a support for the vessel to be exhausted, and a heater surrounding the latter, consisting of two parts, one mounted on an adjustable support, and the other removable to permit insertion and withdrawal of the vessel.

6. A heater for incandescentlamps, comprising a sectional sheet-metal chamber, the removable section having'a heat-insulated handle, said chamber being open at the bottom, a gas-burner beneath the opening, and a deflector to distribute the hot gases.

7. Means-for producing high'vacua, comprising pumping apparatus and a vapor-trap between said apparatus and the lamps or other vessels to be exhausted, consisting of two tubes, one within the other, separably connected, the inner tube being open at the top and containing a drying agent.

8. Means for producing high vacua, comprising pumping apparatus and a trap between said apparatus and a group of lamps to be exhausted, consisting of two tubes, one within the other, separably connected, the outer tube connecting with the several lamps, and the inner tube being provided with openings on its upper side located between the lamp connections.

9. .Means forexhausting lamps, comprising two pumps, a vapor-trap between said pumps and the lamps, compris ing two tubes separably connected, one with in the other, the outer one connectingwith the lamps and the inner containing a drying agent, and connections between the preliminary and final pumps at or near the bottom and top of the outer'tube respectively.

10. Means for producing vacua, comprising two pumps, one for preliminary exhaustion incandescent and the other for final exhaustion, a moisture-trap in the pathof exhaustion, and a liminary pump.

In witness whereof we have hereunto set our hands this 30thday of March, 1900..

JOHN W. HOWELL. W. R. BURROWS. W'itnesses:

. GEO. S. MORRISON, CHAS. H.'HEELEY.

trap for solid refuse in the path to' the. pre 

